Influence of wire electrical discharge conditioning on the grinding performance of metal-bonded diamond grinding tools

Abstract

Wire Electrical Discharge Conditioning (WEDC) is an efficient non-conventional method for conditioning metal, resin, and hybrid bonded super-abrasive grinding tools. Since the diamond and CBN grains are not affected directly by the WEDC and only the electrically conductive bond material is eroded by the process, high grain protrusions are achievable. Therefore, unlike the common mechanical conditioning methods using WEDC, the microtopography of the grinding tool can be influenced by the process parameters, directly affecting the grinding efficiency. However, the selection of WEDC process parameters is influenced by the specifications of the grinding tool, particularly the grain size and concentration. This study aims to investigate the effects of WEDC parameters and strategies on the microtopography and material removal rate of metal-bonded grinding tools, considering different grain sizes and concentrations. Additionally, the correlation between the microtopography of grinding tools conditioned by the WEDC process and their grinding efficiency was investigated by analyzing tool wear, grinding forces, and surface roughness of tungsten carbide workpieces. The results indicate that the material removal rate of the WEDC process decreases as the grain size and concentration of metal-bonded diamond grinding tools increase. Furthermore, it was observed that employing high spark energy parameters reduces the grain protrusion of grinding wheels with small grain sizes. However, the utilization of high-energy sparks is necessary to create larger spark gaps and achieve a higher material removal rate.